Synopsis

The overall goal of this case study is to understand convergence characteristics of Open Knee(s) - Generation 1 model to conduct simulations in an efficient and effective manner.

Use Case

The case relies on simulations of varying levels of tibiofemoral joint loading to evaluate the performance of the model in terms of convergence while reasonably predicting joint mechanics. Convergence is defined by the ease and speed of simulations. Relative predictive accuracy evaluates changes in predicted joint kinematics and tissue stress-strain distributions.

Simulation Aims

To understand the role of joint loading on convergence characteristics

To understand the role of simulation (numerical analysis) parameters on convergence characteristics

To understand model parameters on convergence characteristics

To understand new model features on convergence characteristics

Model

The model is based on Open Knee(s) - Generation 1 model, which was updated for FEBio version 2.1:

Inputs

The loading and boundary conditions relies on prescribed time histories of movement and loading of the tibiofemoral joint (six degrees of freedom) for various loading scenarios (see Simulation Conditions):

flexion

internal/external rotation torque

varus/valgus torque

anterior/posterior force

medial/lateral force

compression/distraction force

Outputs

Convergence metrics (primary)

Completion of simulation (Yes/No)

If not completed - time point at which the simulation crashed

If completed - computation time (also provide computer specifications), number of iterations

Time histories of kinematics-kinetics of the tibiofemoral joint (six degrees of freedom) (secondary)